Single shear for cutting and conveying multiple rolled sections

ABSTRACT

The single shear described herein for cutting and simultaneously conveying one or more pairs of rolling wires or bars includes a mobile diverter consisting of at least two channels in each of which a wire or bar slides. The single shear further includes at least two pairs of counter-knives, each of which acts on the wire or bar, and a conveying device for conveying the cut segments of wires or bars. The conveying device may include at least one pair of mobile elements configured to be independent of each other, but configured to be synchronized with each other and with the mobile diverter for the separate management of each of said cut sections of wires or bars. The single shear may finally include at least two pairs of output channels for conveying the cut segments of wires or bars.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims priority to PCT International ApplicationNo. PCT/EP2014/0715241 filed on Oct. 8, 2014, which application claimspriority to Italian Patent Application No. MI2013A001670 filed Oct. 9,2013, the entirety of the disclosures of which are expresslyincorporated herein by reference.

STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT

Not Applicable.

FIELD OF THE INVENTION

The field of the invention is the production of rolled sections, such aswires or bars, for example by means of a “slit” process.

BACKGROUND ART

Slit plants with two or more wires are used to increase the productionof wires and/or bars. They provide that, after the passage of thestarting billet in one or more rolling cages or units to reach asubstantially rectangular section, the rolled section is slitlongitudinally into two or more equal parts through the passage withinchannels made into specially shaped rolling rollers, making two or morerolled sections which move in parallel and consequently creating two ormore parallel side by side rolling lines.

In the prior art, the two wires that are created through the process oflongitudinal slitting of the rolled section are then processedseparately by means of different machinery. This is mainly due to thephysical and metallurgical differences that each wire or bar has, withthe consequent need to separate the rolled wires or bars to be able toensure a homogeneous and uniform processing thereof. The two wire slitthus allows increasing the production but also entails a considerablyhigher cost as regards the machinery, the related spares and themaintenance of what is located downstream of the slitting.

An essential aspect for the cutting and management of the rolling wiresor bars consists of the speed and effectiveness of the shear, which mustslit with precision and subsequently convey the sections thus obtainedwithout undergoing hitches of a mechanical nature. In the plantscurrently in operation this aspect, linked to the increasingly growingproduction, has now taken primary importance and the necessity of havingto use a shear for each wire or bar therefore is a considerablelimitation and an increase of complexity for both the plant and for theeffectiveness of the process itself.

An example of a single machinery to process the two lines is known fromdocument EP0773082, which describes a single shear which cuts twoparallel wires. However, the two wires are kept spaced apart and the twolines are separate, thus requiring separate equipment upstream anddownstream for the two wires.

Also U.S. Pat. No. 4,966,060 refers to a high-speed shear system forcutting rolling wires or bars wherein a pair of cutting knives acts oneach wire or bar while a specially shaped partitioning template allowsthe cut section of wire to enter output channels. However, the choice ofthe output channel is governed by the lateral mechanical displacement ofthe guide, thus slowing down the separation process and with the highrisk that the cut wire enters the wrong output channel, or even worse,gets stuck between the partitioning template and the guide itself, thuslocking the plant.

Another system for cutting rolling wires is disclosed in document U.S.Pat. No. 5,644,941, which describes a system for cooling and cuttingsingle wires or rods by means of facing pairs of knives. Also in thiscase, the system is rather complex basically due to the fact that everysingle wire must be slit and conveyed separately to the output guides,with issues related to the management and the spacing between one wireand the other.

Finally, also U.S. Pat. No. 6,684,745 describes a shear for cuttingrolling wires or bars which has, for each of them, different series ofcoupled knives and a complex system of guides for the management of thecutting and the positioning of the wires themselves. Also for thissolution, the major problems are found in the multiplicity of devices incase of different wires and in the difficult management of the cuttingtails in output from the shear, which must be conveyed individually inthe respective separation channels.

SUMMARY OF THE INVENTION

On the basis of the limitations and problems encountered in the priorart shear systems and plants, it is a primary object of the presentinvention to provide a single shear which allows cutting to size twoadjacent and parallel wires with single machinery.

Another object of the present invention is to provide a shear forcutting to size which could be inserted in a line that processes twoadjacent and parallel wires together, produced by the slit process orcoming from two separate lines.

A further object of the invention is to provide a shear that is able toseamlessly manage the cutting and the subsequent distribution of the cutwire or bar heads within output channels, even in a high-speed cuttingcondition.

These and other objects are achieved by a single shear for cutting andsimultaneously conveying one or more pairs of rolling wires or barswhich, according to claim 1, comprises the following parts:

a) a mobile diverter consisting of at least two channels in each ofwhich a wire or bar can slide;

b) at least two pairs of counter-rotating knives, each pair ofcounter-rotating knives acting on a respective wire or bar producingrespective segments of wire or bar;

c) a conveying device for conveying the segments of wire or bar,comprising

-   -   at least two pairs of output channels for conveying the segments        of wire or bar,    -   at least one pair of mobile elements configured so as to be        independent of each other and synchronized with each other and        with the mobile diverter for a separate management of each of        said segments of wire or bar so as to facilitate the insertion        of each segment of wire or bar in a respective output channel of        said pairs of output channels.

According to another aspect of the invention, the problems mentionedabove are solved by means of a method of cutting and conveying rollingwires or bars making use of the shears described herein which, accordingto claim 10, comprises the following sequence of steps:

a) providing the diverter in a first conveying position, andsimultaneously lowering a first mobile element up to a total opening ofa respective first central channel and raising a second mobile elementup to a total closing of a second central channel;

b) moving the diverter in a first direction towards a cutting position,intermediate between said first conveying position and a secondconveying position, and simultaneously raising the first mobile elementup to a partial closure of the first central channel and lowering thesecond mobile element up to a partial opening of the second centralchannel;

c) moving the diverter in said first direction up to reaching saidsecond conveying position, and simultaneously raising the first mobileelement up to a total closure of the first central channel and loweringthe second mobile element up to a total opening of the second centralchannel;

d) moving the diverter in a second direction, opposite to the firstdirection, towards the cutting position, and simultaneously lowering thefirst mobile element up to a partial opening of the first centralchannel and raising the second mobile element up to a partial closure ofthe second central channel;

e) moving the diverter in said first direction up to reaching said firstconveying position;

f) repeating steps a)-e).

In the following description, it is understood that the term wire, forreasons of brevity, also refers to the rolled bar product. Moreover, atwo-wire slit process is taken as an example but it is understood thatthe invention also refers without distinction to the cutting of multipleparallel wires not coming from a slit process or to the cutting ofthree, four, five or more wires coming from a slit process.

The single shear according to the present invention offers thepossibility of cutting to commercial size two or more adjacent andparallel wires and, therefore, of simultaneously managing differentsliding lines without the need to adopt multiple and specific solutionsfor each rolling product. Moreover, the synchronization between themobile diverter and the conveying device allows obtaining a rapid andeffective separation of the cutting heads without the risk that they canenter wrong output channels or, even worse, come into contact with oneanother with consequent locking of the entire plant.

The particular configuration of the mobile conveying elements accordingto the present invention offers a double advantage: on the one hand,they have sliding surfaces configured so as to guide the displacement ofthe wires after cutting, thus favoring the proper conveying thereof and,at the same time, they constitute actual elements for opening andclosing the output channels of the cut wires, which make thedistribution of the cut sections effective and safe even in high-speedcondition. This therefore allows the management of a larger number ofwires in a single cutting process without mechanical or structurallimitations of any kind.

BRIEF DESCRIPTION OF THE FIGURES

Further features and advantages of the invention will be more apparentin light of the detailed description of a preferred, but not exclusive,embodiment of a single shear according to the present invention for atwo-wire production plant, shown by way of a non-limiting example withthe aid of the accompanying drawings, in which:

FIG. 1a shows a schematic top view of all the components of the shear ina first conveying position of the wires;

FIG. 1b shows a schematic top view of all the components of the shear ina position where the wires are cut;

FIG. 1c shows a schematic top view of all the components of the shear ina second conveying position of the wires;

FIG. 2 shows a schematic representation of one of the mobile conveyingelements;

FIG. 3a shows the position of the mobile conveying elements during theopening and closing steps of the output channels of the wirescorresponding to the position in FIG. 1 a.

FIG. 3b shows the position of the mobile conveying elements during theopening and closing steps of the output channels of the wirescorresponding to the position in FIG. 1 b.

FIG. 3c shows the position of the mobile conveying elements during theopening and closing steps of the output channels of the wirescorresponding to the position in FIG. 1 c.

Same reference numerals in the various figures correspond to the sameelements or components.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

The component parts of the shears of the present invention are shown inFIG. 1.

The shear consists of two knife-holding drums, an upper one and a lowerone, on each of which at least two pairs of counter-rotating knives 3, 4are arranged, each arranged for cutting to size one of the two wires 1,2.

Diverter 5 upstream of the two knife-holding drums, includes twochannels 6, 7 in each of which a wire slides; diverter 5 switches from afirst conveying position A to a second conveying position B and viceversa, so that the wires are cut during this movement, at anintermediate cutting position T between positions A and B, wherein wires1, 2 cross the counter-rotating knives 3, 4.

On the side distal to diverter 5, downstream of the knife-holding drums,the shear has a conveying device 9 having four separate output channelsA1, A2, B1 and B2 in which the segments of wire cut to size are entered.

According to a preferred configuration of the invention, the conveyingdevice 9 comprises a lower surface 18, defining a base of the device, anupper surface 19 which delimits the height of the output channels, andtwo outer lateral walls 10, 10′, which connect the lower surface 18 tothe upper surface 19 and which extend as close as possible to thecutting area for conveying the heads of the wire segments just cut inthe correct channel.

A first pair of output channels includes:

-   -   a first lateral channel A1, or first outer channel, delimited by        the outer lateral wall 10 and by an intermediate partition 11;    -   and a first central channel A2, or first inner channel,        delimited by the intermediate partition 11 and by a central        partition 12.

A second pair of output channels includes:

-   -   a second central channel B1, or second inner channel, delimited        by the central partition 12 and by an intermediate partition        11′;    -   and a second lateral channel B2, or second outer channel,        delimited by the intermediate partition 11′ and by the outer        lateral wall 10′.

The central channels A2 and B1 are adjacent and are separated from eachother by the central partition 12.

When diverter 5 is in position A, as shown in FIG. 1a , wire 1 continuesits run in the lateral channel A1, while wire 2 does so in the centralchannel A2.

When diverter 5 moves to the right to reach position B, at theintermediate position T (FIG. 1b ), wire 1 is cut by a pair of knives 3while wire 2 is cut by a pair of knives 4; the tails of the wiresegments just cut continue in channels A1 and A2 while the new heads ofthe two wires 1 and 2, continuing the displacement of diverter 5 to theright, reach and continue in channels B1 and B2.

Therefore, when diverter 5 is in position B, as shown in FIG. 1c , wire1 continues its run in the central channel B1, while wire 2 does so inthe lateral channel B2. Diverter 5 remains in position B up to a newdisplacement to the left, and thus a new cut at the intermediateposition T (FIG. 1b ).

To prevent the heads of the wires just cut from entering the wrongcentral channel, the path thereof is advantageously constrained withindependently mobile elements 20, 20, synchronized with each other andwith diverter 5. FIG. 1 shows where these elements 20, 20′ arepreferably positioned inside the conveying device 9, while FIG. 2schematically shows a possible shape of the mobile element 20. Themobile element 20 is positioned before the central channel A2, while themobile element 20′ is positioned before the central channel B1. Bothsaid mobile elements 20, 20′ are positioned (FIG. 1) in a central frontarea of device 9 between the outer lateral walls 10, 10′.

According to a preferred variant of the invention, the two mobileelements 20, 20′ arranged mirror-wise with each other, are synchronizedto move vertically, in the direction opposite to each other, andalternately open and close the two central channels A2 and B1 accordingto the position of diverter 5.

The mobile elements 20, 20′ used in the shears according to the presentinvention include:

-   -   a lateral containment wall 14, 14′, arranged substantially        vertically;    -   a sliding surface 15, 15′ for the wires entering the conveying        device 9, arranged transversely to said lateral containment wall        14, 14′,    -   a conveying surface 16, 16′ inclined with respect to the lateral        containment wall 14, 14′, and also arranged substantially        vertically.

The sliding surface 15 and the conveying surface 16 are outer surfacesof a wedge-shaped element having its base resting on the lateralcontainment wall 14.

The thickness of said wedge-shaped element is minimum at the entranceside of the wires in the conveying device 9, i.e. at the front end ofthe lateral containment wall 14.

More in detail, the first lateral channel A1 is delimited on one side bythe outer lateral wall 10, and on the other side initially by thelateral containment wall 14 and then by the intermediate partition 11;while the second lateral channel B2 is delimited on one side by theouter lateral wall 10′ and on the other side initially by the lateralcontainment wall 14′ and then by the intermediate partition 11′.

Advantageously, the sliding surfaces 15, 15′ may be inclined downwards,starting from the inlet side of the wires or bars 1, 2, in order toaccompany the wire or bar 1, 2 towards the corresponding central outputchannel A2, B1.

Preferably, the height of the lateral containment wall 14, 14′ of themobile elements 20, 20′ is greater than or equal to the distance betweenthe lower surface 18 and the upper surface 19 of the conveying device 9.

Moreover, the height of the conveying surface 16, 16′ is preferablyequal to the height of the portion of lateral containment wall 14, 14′not covered by the wedge-shaped element.

The typical operation of the mobile elements 20, 20′ is schematicallyshown in FIG. 3. It is the basis of the method of cutting and conveyingrolling wires or bars using the shears according to the presentinvention. According to a preferred embodiment, such a method is carriedout as follows.

Diverter 5 is placed in the first conveying position A and,simultaneously, the mobile element 20 is lowered up to a total openingof the respective central channel A2, with separation of channels A1 andA2 through the lateral containment wall 14, and the mobile element 20′is raised up to a total closing of channel B1. In this configuration,the wires or bars 1, 2 slide within channels A1 and A2.

Thereafter, after a predetermined time interval based on the advancementspeed of the wires and the desired cutting length of the wire segments,deviator 5 is moved to position B; during the passage between position Aand position B, the diverter passes by the intermediate cutting positionT and there occurs a gradual change of position of the mobile elements20, 20′. More in detail, the mobile element 20 rises up to a partialclosure of the central channel A2, while the mobile element 20′ islowered up to a partial opening of the central channel B1. Preferably,at the intermediate cutting position T of diverter 5, the mobileelements 20, 20′ are at the same height, as shown in FIG. 3c . Due tothe inclination of the sliding surface 15, the tail of the segment ofwire 2, just cut, is always accompanied towards the central channel A2.

When diverter 5 reaches position B, at the same time, the mobile element20 is raised up to a total closure of channel A2, and the mobile element20′ is lowered up to a total opening of channel B1 with separation ofchannels B1 and B2 through the lateral containment wall 14′. In thisconfiguration, the wires or bars 1, 2 slide within channels B1 and B2.

Thereafter, after the above predetermined time interval, deviator 5 ismoved to position A; during the passage between position B and positionA, the diverter again passes by the intermediate cutting position T andthere occurs a gradual change of position of the mobile elements 20,20′. The mobile element 20 lowers up to a partial opening of the centralchannel A2, while the mobile element 20 raises up to a partial closureof the central channel B1. Preferably, at the intermediate cuttingposition T of diverter 5, the mobile elements 20, 20′ are at the sameheight, as shown in FIG. 3c . Due to the inclination of the slidingsurface 15′, the tail of the segment of wire 1, just cut, is alwaysaccompanied towards the central channel B1.

When diverter 5 reaches position A, the process restarts by carrying outagain the above steps.

A better understanding of the cutting steps can be obtained by referringto FIGS. 3a, 3b and 3 c.

When diverter 5 is in position A, corresponding to FIG. 3a , and thusthe two wires 1, 2 run through channels A1 and A2, the mobile element 20is lowered to leave channel A2 open, while the mobile element 20′ israised to close channel B1 and for the lateral surface 16′ thereof tobehave like a conveying wall of wire 2 towards channel A2.

When diverter 5 moves to reach position B, the two wires 1, 2 are cutoften at the intermediate cutting position T of diverter 5, while thetwo mobile elements 20, 20′ are moving in mutually opposite direction tochange their position. This intermediate situation is shown in FIG. 3b .The sliding surface 15 of the mobile element 20 can advantageously beinclined downward, entering the respective central output channel, toprevent the tail of the segment of wire or bar from becoming jammedbetween the same surface 15 that is rising and the upper surface 19which superiorly delimits all the channels.

When diverter 5 reaches position B (FIG. 3c ), the two wires 1, 2 runthrough channels B1 and B2; the mobile element 20 c is in loweredposition leaving channel B1 open; the mobile element 20 is raised toclose channel A2 and for the lateral surface 16 thereof to behave like aconveying wall of wire 1 towards channel B1.

At this point, diverter 5 will once again begin to move toward positionA, passing by the intermediate cutting position T, and the cycle of theabove steps will start again.

In the light of the invention described herein, it is thus possible toobtain several advantages compared to what has been used so far in theprior art. Such advantages may be essentially summarized as follows:

-   -   it is possible to have a single machinery that replaces two or        more shears,    -   a single diverter can be used which adjusts the position of two        wires,    -   a single equipment can be used which processes and distributes        all the segments cut from the starting wires and, finally, the        cutting to size of two parallel wires or bars can be carried out        even at very small distances even in high-speed condition of the        same bars.

The invention claimed is:
 1. A method of cutting and conveying rollingwires or bars using a shear, the shear for cutting and simultaneouslyconveying the wires or bars and comprising: i) a mobile divertercomprising at least two channels in each of which one of the wires orbars can slide; ii) counter-rotating knives acting on the wires or bars,thus producing one or more pairs of segments of wire or bar; and iii) aconveying device for conveying the one or more pairs of segments of wireor bar, comprising at least two pairs of output channels for conveyingthe one or more pairs of segments of wire or bar, and at least one pairof mobile elements that are independent of each other and synchronizedwith each other and with the mobile diverter so as to separately manageeach segment of said one or more pairs of segments of wire or bar andinsert each segment in a respective output channel of said at least twopairs of output channels, wherein the mobile diverter is configured totake: a first conveying position at which the wires or bars are conveyedin a first pair of the at least two pairs of output channels; a secondconveying position at which the wires or bars are conveyed in a secondpair of the at least two pairs of output channels; and an intermediatecutting position, between the first conveying position and the secondconveying position, at which the wires or bars come into contact withthe counter-rotating knives; and wherein a first mobile element of saidat least one pair of mobile elements is positioned at an entrance of afirst central output channel of said first pair of said at least twopairs of output channels, and a second mobile element of said at leastone pair of mobile elements is positioned at an entrance of a secondcentral output channel of said second pair of said at least two pairs ofoutput channels, said second central output channel being adjacent tothe first central output channel; the method comprising the followingsequence of steps: a) providing the mobile diverter in said firstconveying position, and simultaneously lowering said first mobileelement up to a total opening of said first central output channel andraising said second mobile element up to a total closing of said secondcentral output channel; b) moving the mobile diverter in a firstdirection towards the intermediate cutting position, and simultaneouslyraising the first mobile element up to a partial closure of the firstcentral output channel and lowering the second mobile element up to apartial opening of the second central output channel; c) moving themobile diverter in said first direction up to reaching said secondconveying position, and simultaneously raising the first mobile elementup to a total closure of the first central output channel and loweringthe second mobile element up to a total opening of the second centraloutput channel; d) moving the mobile diverter in a second direction,opposite to the first direction, towards the intermediate cuttingposition, and simultaneously lowering the first mobile element up to apartial opening of the first central output channel and raising thesecond mobile element up to a partial closure of the second centraloutput channel; e) moving the mobile diverter in said second directionup to reaching said first conveying position; f) repeating steps a)-e).2. A method according to claim 1, wherein in step a) the wires or barsslide inside the first pair of the at least two pairs of outputchannels; and in step c) the wires or bars slide inside the second pairof the at least two pairs of output channels.
 3. A method according toclaim 1, wherein in step b) and in step d), at the cutting position, thefirst mobile element and the second mobile element are at a same height.